/*******************************************************************************
 *     ___                  _   ____  ____
 *    / _ \ _   _  ___  ___| |_|  _ \| __ )
 *   | | | | | | |/ _ \/ __| __| | | |  _ \
 *   | |_| | |_| |  __/\__ \ |_| |_| | |_) |
 *    \__\_\\__,_|\___||___/\__|____/|____/
 *
 *  Copyright (c) 2014-2019 Appsicle
 *  Copyright (c) 2019-2024 QuestDB
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 ******************************************************************************/

package io.questdb.griffin.engine.functions.array;

import io.questdb.cairo.CairoConfiguration;
import io.questdb.cairo.arr.ArrayView;
import io.questdb.cairo.arr.DerivedArrayView;
import io.questdb.cairo.sql.Function;
import io.questdb.cairo.sql.Record;
import io.questdb.cairo.sql.SymbolTableSource;
import io.questdb.cairo.sql.WeakDimsArrayFunction;
import io.questdb.griffin.FunctionFactory;
import io.questdb.griffin.PlanSink;
import io.questdb.griffin.SqlException;
import io.questdb.griffin.SqlExecutionContext;
import io.questdb.griffin.engine.functions.UnaryFunction;
import io.questdb.std.IntList;
import io.questdb.std.ObjList;
import io.questdb.std.Transient;

public class DoubleArrayTransposeFunctionFactory implements FunctionFactory {

    @Override
    public String getSignature() {
        return "transpose(D[])";
    }

    @Override
    public Function newInstance(
            int position,
            @Transient ObjList<Function> args,
            @Transient IntList argPositions,
            CairoConfiguration configuration,
            SqlExecutionContext sqlExecutionContext
    ) throws SqlException {
        return new Func(args.getQuick(0), position);
    }

    private static class Func extends WeakDimsArrayFunction implements UnaryFunction {
        private final Function arrayArg;
        private final DerivedArrayView borrowedView = new DerivedArrayView();

        public Func(Function arrayArg, int position) {
            this.arrayArg = arrayArg;
            this.type = arrayArg.getType();
            this.position = position;
        }

        @Override
        public Function getArg() {
            return arrayArg;
        }

        @Override
        public ArrayView getArray(Record rec) {
            ArrayView array = arrayArg.getArray(rec);
            borrowedView.of(array);
            borrowedView.transpose();
            return borrowedView;
        }

        @Override
        public void init(SymbolTableSource symbolTableSource, SqlExecutionContext executionContext) throws SqlException {
            UnaryFunction.super.init(symbolTableSource, executionContext);
            this.type = arrayArg.getType();
            validateAssignedType();
        }

        @Override
        public boolean isThreadSafe() {
            return false;
        }

        @Override
        public void toPlan(PlanSink sink) {
            sink.val("transpose(").val(arrayArg).val(')');
        }
    }
}
